/*
 * Copyright (c) 2009, 2011 CTTC
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 * Author: Nicola Baldo <nbaldo@cttc.es>
 *         Giuseppe Piro  <g.piro@poliba.it>
 *         Marco Miozzo <marco.miozzo@cttc.es> (add physical error model)
 */

#include "lte-spectrum-phy.h"

#include "lte-chunk-processor.h"
#include "lte-control-messages.h"
#include "lte-mi-error-model.h"
#include "lte-radio-bearer-tag.h"
#include "lte-spectrum-signal-parameters.h"

#include "ns3/antenna-model.h"
#include "ns3/boolean.h"
#include "ns3/config.h"
#include "ns3/double.h"
#include "ns3/log.h"
#include "ns3/object-factory.h"
#include "ns3/simulator.h"
#include "ns3/trace-source-accessor.h"

#include <cmath>

namespace ns3
{

NS_LOG_COMPONENT_DEFINE("LteSpectrumPhy");

/// duration of SRS portion of UL subframe
/// = 1 symbol for SRS -1ns as margin to avoid overlapping simulator events
static const Time UL_SRS_DURATION = NanoSeconds(71429 - 1);

/// duration of the control portion of a subframe
/// = 0.001 / 14 * 3 (ctrl fixed to 3 symbols) -1ns as margin to avoid overlapping simulator events
static const Time DL_CTRL_DURATION = NanoSeconds(214286 - 1);

/// Effective coding rate
static const double EffectiveCodingRate[29] = {
    0.08, 0.1, 0.11, 0.15, 0.19, 0.24, 0.3, 0.37, 0.44, 0.51, 0.3, 0.33, 0.37, 0.42, 0.48,
    0.54, 0.6, 0.43, 0.45, 0.5,  0.55, 0.6, 0.65, 0.7,  0.75, 0.8, 0.85, 0.89, 0.92,
};

TbId_t::TbId_t()
{
}

TbId_t::TbId_t(const uint16_t a, const uint8_t b)
    : m_rnti(a),
      m_layer(b)
{
}

/**
 * Equality operator
 *
 * @param a lhs
 * @param b rhs
 * @returns true if rnti and layer are equal
 */
bool
operator==(const TbId_t& a, const TbId_t& b)
{
    return ((a.m_rnti == b.m_rnti) && (a.m_layer == b.m_layer));
}

/**
 * Less than operator
 *
 * @param a lhs
 * @param b rhs
 * @returns true if rnti less than ro rnti equal and layer less than
 */
bool
operator<(const TbId_t& a, const TbId_t& b)
{
    return ((a.m_rnti < b.m_rnti) || ((a.m_rnti == b.m_rnti) && (a.m_layer < b.m_layer)));
}

NS_OBJECT_ENSURE_REGISTERED(LteSpectrumPhy);

LteSpectrumPhy::LteSpectrumPhy()
    : m_state(IDLE),
      m_cellId(0),
      m_componentCarrierId(0),
      m_transmissionMode(0),
      m_layersNum(1)
{
    NS_LOG_FUNCTION(this);
    m_random = CreateObject<UniformRandomVariable>();
    m_random->SetAttribute("Min", DoubleValue(0.0));
    m_random->SetAttribute("Max", DoubleValue(1.0));
    m_interferenceData = CreateObject<LteInterference>();
    m_interferenceCtrl = CreateObject<LteInterference>();

    for (uint8_t i = 0; i < 7; i++)
    {
        m_txModeGain.push_back(1.0);
    }
}

LteSpectrumPhy::~LteSpectrumPhy()
{
    NS_LOG_FUNCTION(this);
    m_expectedTbs.clear();
    m_txModeGain.clear();
}

void
LteSpectrumPhy::DoDispose()
{
    NS_LOG_FUNCTION(this);
    m_channel = nullptr;
    m_mobility = nullptr;
    m_device = nullptr;
    m_interferenceData->Dispose();
    m_interferenceData = nullptr;
    m_interferenceCtrl->Dispose();
    m_interferenceCtrl = nullptr;
    m_ltePhyRxDataEndErrorCallback = MakeNullCallback<void>();
    m_ltePhyRxDataEndOkCallback = MakeNullCallback<void, Ptr<Packet>>();
    m_ltePhyRxCtrlEndOkCallback = MakeNullCallback<void, std::list<Ptr<LteControlMessage>>>();
    m_ltePhyRxCtrlEndErrorCallback = MakeNullCallback<void>();
    m_ltePhyDlHarqFeedbackCallback = MakeNullCallback<void, DlInfoListElement_s>();
    m_ltePhyUlHarqFeedbackCallback = MakeNullCallback<void, UlInfoListElement_s>();
    m_ltePhyRxPssCallback = MakeNullCallback<void, uint16_t, Ptr<SpectrumValue>>();
    SpectrumPhy::DoDispose();
}

/**
 * Output stream output operator
 *
 * @param os output stream
 * @param s state
 * @returns output stream
 */
std::ostream&
operator<<(std::ostream& os, LteSpectrumPhy::State s)
{
    switch (s)
    {
    case LteSpectrumPhy::IDLE:
        os << "IDLE";
        break;
    case LteSpectrumPhy::RX_DATA:
        os << "RX_DATA";
        break;
    case LteSpectrumPhy::RX_DL_CTRL:
        os << "RX_DL_CTRL";
        break;
    case LteSpectrumPhy::TX_DATA:
        os << "TX_DATA";
        break;
    case LteSpectrumPhy::TX_DL_CTRL:
        os << "TX_DL_CTRL";
        break;
    case LteSpectrumPhy::TX_UL_SRS:
        os << "TX_UL_SRS";
        break;
    default:
        os << "UNKNOWN";
        break;
    }
    return os;
}

TypeId
LteSpectrumPhy::GetTypeId()
{
    static TypeId tid =
        TypeId("ns3::LteSpectrumPhy")
            .SetParent<SpectrumPhy>()
            .SetGroupName("Lte")
            .AddTraceSource("TxStart",
                            "Trace fired when a new transmission is started",
                            MakeTraceSourceAccessor(&LteSpectrumPhy::m_phyTxStartTrace),
                            "ns3::PacketBurst::TracedCallback")
            .AddTraceSource("TxEnd",
                            "Trace fired when a previously started transmission is finished",
                            MakeTraceSourceAccessor(&LteSpectrumPhy::m_phyTxEndTrace),
                            "ns3::PacketBurst::TracedCallback")
            .AddTraceSource("RxStart",
                            "Trace fired when the start of a signal is detected",
                            MakeTraceSourceAccessor(&LteSpectrumPhy::m_phyRxStartTrace),
                            "ns3::PacketBurst::TracedCallback")
            .AddTraceSource("RxEndOk",
                            "Trace fired when a previously started RX terminates successfully",
                            MakeTraceSourceAccessor(&LteSpectrumPhy::m_phyRxEndOkTrace),
                            "ns3::Packet::TracedCallback")
            .AddTraceSource("RxEndError",
                            "Trace fired when a previously started RX terminates with an error",
                            MakeTraceSourceAccessor(&LteSpectrumPhy::m_phyRxEndErrorTrace),
                            "ns3::Packet::TracedCallback")
            .AddAttribute("DataErrorModelEnabled",
                          "Activate/Deactivate the error model of data (TBs of PDSCH and PUSCH) "
                          "[by default is active].",
                          BooleanValue(true),
                          MakeBooleanAccessor(&LteSpectrumPhy::m_dataErrorModelEnabled),
                          MakeBooleanChecker())
            .AddAttribute("CtrlErrorModelEnabled",
                          "Activate/Deactivate the error model of control (PCFICH-PDCCH "
                          "decodification) [by default is active].",
                          BooleanValue(true),
                          MakeBooleanAccessor(&LteSpectrumPhy::m_ctrlErrorModelEnabled),
                          MakeBooleanChecker())
            .AddTraceSource("DlPhyReception",
                            "DL reception PHY layer statistics.",
                            MakeTraceSourceAccessor(&LteSpectrumPhy::m_dlPhyReception),
                            "ns3::PhyReceptionStatParameters::TracedCallback")
            .AddTraceSource("UlPhyReception",
                            "DL reception PHY layer statistics.",
                            MakeTraceSourceAccessor(&LteSpectrumPhy::m_ulPhyReception),
                            "ns3::PhyReceptionStatParameters::TracedCallback");
    return tid;
}

Ptr<NetDevice>
LteSpectrumPhy::GetDevice() const
{
    NS_LOG_FUNCTION(this);
    return m_device;
}

Ptr<MobilityModel>
LteSpectrumPhy::GetMobility() const
{
    NS_LOG_FUNCTION(this);
    return m_mobility;
}

void
LteSpectrumPhy::SetDevice(Ptr<NetDevice> d)
{
    NS_LOG_FUNCTION(this << d);
    m_device = d;
}

void
LteSpectrumPhy::SetMobility(Ptr<MobilityModel> m)
{
    NS_LOG_FUNCTION(this << m);
    m_mobility = m;
}

void
LteSpectrumPhy::SetChannel(Ptr<SpectrumChannel> c)
{
    NS_LOG_FUNCTION(this << c);
    m_channel = c;
}

Ptr<SpectrumChannel>
LteSpectrumPhy::GetChannel()
{
    return m_channel;
}

Ptr<const SpectrumModel>
LteSpectrumPhy::GetRxSpectrumModel() const
{
    return m_rxSpectrumModel;
}

void
LteSpectrumPhy::SetTxPowerSpectralDensity(Ptr<SpectrumValue> txPsd)
{
    NS_LOG_FUNCTION(this << txPsd);
    NS_ASSERT(txPsd);
    m_txPsd = txPsd;
}

void
LteSpectrumPhy::SetNoisePowerSpectralDensity(Ptr<const SpectrumValue> noisePsd)
{
    NS_LOG_FUNCTION(this << noisePsd);
    NS_ASSERT(noisePsd);
    m_rxSpectrumModel = noisePsd->GetSpectrumModel();
    m_interferenceData->SetNoisePowerSpectralDensity(noisePsd);
    m_interferenceCtrl->SetNoisePowerSpectralDensity(noisePsd);
}

void
LteSpectrumPhy::Reset()
{
    NS_LOG_FUNCTION(this);
    m_cellId = 0;
    m_state = IDLE;
    m_transmissionMode = 0;
    m_layersNum = 1;
    m_endTxEvent.Cancel();
    m_endRxDataEvent.Cancel();
    m_endRxDlCtrlEvent.Cancel();
    m_endRxUlSrsEvent.Cancel();
    m_rxControlMessageList.clear();
    m_expectedTbs.clear();
    m_txControlMessageList.clear();
    m_rxPacketBurstList.clear();
    m_txPacketBurst = nullptr;
    m_rxSpectrumModel = nullptr;

    // Detach from the channel, because receiving any signal without
    // spectrum model is an error.
    if (m_channel)
    {
        m_channel->RemoveRx(this);
    }
}

void
LteSpectrumPhy::SetLtePhyRxDataEndErrorCallback(LtePhyRxDataEndErrorCallback c)
{
    NS_LOG_FUNCTION(this);
    m_ltePhyRxDataEndErrorCallback = c;
}

void
LteSpectrumPhy::SetLtePhyRxDataEndOkCallback(LtePhyRxDataEndOkCallback c)
{
    NS_LOG_FUNCTION(this);
    m_ltePhyRxDataEndOkCallback = c;
}

void
LteSpectrumPhy::SetLtePhyRxCtrlEndOkCallback(LtePhyRxCtrlEndOkCallback c)
{
    NS_LOG_FUNCTION(this);
    m_ltePhyRxCtrlEndOkCallback = c;
}

void
LteSpectrumPhy::SetLtePhyRxCtrlEndErrorCallback(LtePhyRxCtrlEndErrorCallback c)
{
    NS_LOG_FUNCTION(this);
    m_ltePhyRxCtrlEndErrorCallback = c;
}

void
LteSpectrumPhy::SetLtePhyRxPssCallback(LtePhyRxPssCallback c)
{
    NS_LOG_FUNCTION(this);
    m_ltePhyRxPssCallback = c;
}

void
LteSpectrumPhy::SetLtePhyDlHarqFeedbackCallback(LtePhyDlHarqFeedbackCallback c)
{
    NS_LOG_FUNCTION(this);
    m_ltePhyDlHarqFeedbackCallback = c;
}

void
LteSpectrumPhy::SetLtePhyUlHarqFeedbackCallback(LtePhyUlHarqFeedbackCallback c)
{
    NS_LOG_FUNCTION(this);
    m_ltePhyUlHarqFeedbackCallback = c;
}

Ptr<Object>
LteSpectrumPhy::GetAntenna() const
{
    return m_antenna;
}

void
LteSpectrumPhy::SetAntenna(Ptr<AntennaModel> a)
{
    NS_LOG_FUNCTION(this << a);
    m_antenna = a;
}

void
LteSpectrumPhy::SetState(State newState)
{
    ChangeState(newState);
}

void
LteSpectrumPhy::ChangeState(State newState)
{
    NS_LOG_LOGIC(this << " state: " << m_state << " -> " << newState);
    m_state = newState;
}

void
LteSpectrumPhy::SetHarqPhyModule(Ptr<LteHarqPhy> harq)
{
    m_harqPhyModule = harq;
}

bool
LteSpectrumPhy::StartTxDataFrame(Ptr<PacketBurst> pb,
                                 std::list<Ptr<LteControlMessage>> ctrlMsgList,
                                 Time duration)
{
    NS_LOG_FUNCTION(this << pb);
    NS_LOG_LOGIC(this << " state: " << m_state);

    m_phyTxStartTrace(pb);

    switch (m_state)
    {
    case RX_DATA:
    case RX_DL_CTRL:
    case RX_UL_SRS:
        NS_FATAL_ERROR("cannot TX while RX: according to FDD channel access, the physical layer "
                       "for transmission cannot be used for reception");
        break;

    case TX_DATA:
    case TX_DL_CTRL:
    case TX_UL_SRS:
        NS_FATAL_ERROR("cannot TX while already TX: the MAC should avoid this");
        break;

    case IDLE: {
        /*
        m_txPsd must be set by the device, according to
        (i) the available subchannel for transmission
        (ii) the power transmission
        */
        NS_ASSERT(m_txPsd);
        m_txPacketBurst = pb;

        // we need to convey some PHY meta information to the receiver
        // to be used for simulation purposes (e.g., the CellId). This
        // is done by setting the ctrlMsgList parameter of
        // LteSpectrumSignalParametersDataFrame
        ChangeState(TX_DATA);
        NS_ASSERT(m_channel);
        Ptr<LteSpectrumSignalParametersDataFrame> txParams =
            Create<LteSpectrumSignalParametersDataFrame>();
        txParams->duration = duration;
        txParams->txPhy = GetObject<SpectrumPhy>();
        txParams->txAntenna = m_antenna;
        txParams->psd = m_txPsd;
        txParams->packetBurst = pb;
        txParams->ctrlMsgList = ctrlMsgList;
        txParams->cellId = m_cellId;
        m_channel->StartTx(txParams);
        m_endTxEvent = Simulator::Schedule(duration, &LteSpectrumPhy::EndTxData, this);
    }
        return false;

    default:
        NS_FATAL_ERROR("unknown state");
        return true;
    }
}

bool
LteSpectrumPhy::StartTxDlCtrlFrame(std::list<Ptr<LteControlMessage>> ctrlMsgList, bool pss)
{
    NS_LOG_FUNCTION(this << " PSS " << (uint16_t)pss);
    NS_LOG_LOGIC(this << " state: " << m_state);

    switch (m_state)
    {
    case RX_DATA:
    case RX_DL_CTRL:
    case RX_UL_SRS:
        NS_FATAL_ERROR("cannot TX while RX: according to FDD channel access, the physical layer "
                       "for transmission cannot be used for reception");
        break;

    case TX_DATA:
    case TX_DL_CTRL:
    case TX_UL_SRS:
        NS_FATAL_ERROR("cannot TX while already TX: the MAC should avoid this");
        break;

    case IDLE: {
        /*
        m_txPsd must be set by the device, according to
        (i) the available subchannel for transmission
        (ii) the power transmission
        */
        NS_ASSERT(m_txPsd);

        // we need to convey some PHY meta information to the receiver
        // to be used for simulation purposes (e.g., the CellId). This
        // is done by setting the cellId parameter of
        // LteSpectrumSignalParametersDlCtrlFrame
        ChangeState(TX_DL_CTRL);
        NS_ASSERT(m_channel);

        Ptr<LteSpectrumSignalParametersDlCtrlFrame> txParams =
            Create<LteSpectrumSignalParametersDlCtrlFrame>();
        txParams->duration = DL_CTRL_DURATION;
        txParams->txPhy = GetObject<SpectrumPhy>();
        txParams->txAntenna = m_antenna;
        txParams->psd = m_txPsd;
        txParams->cellId = m_cellId;
        txParams->pss = pss;
        txParams->ctrlMsgList = ctrlMsgList;
        m_channel->StartTx(txParams);
        m_endTxEvent = Simulator::Schedule(DL_CTRL_DURATION, &LteSpectrumPhy::EndTxDlCtrl, this);
    }
        return false;

    default:
        NS_FATAL_ERROR("unknown state");
        return true;
    }
}

bool
LteSpectrumPhy::StartTxUlSrsFrame()
{
    NS_LOG_FUNCTION(this);
    NS_LOG_LOGIC(this << " state: " << m_state);

    switch (m_state)
    {
    case RX_DATA:
    case RX_DL_CTRL:
    case RX_UL_SRS:
        NS_FATAL_ERROR("cannot TX while RX: according to FDD channel access, the physical layer "
                       "for transmission cannot be used for reception");
        break;

    case TX_DL_CTRL:
    case TX_DATA:
    case TX_UL_SRS:
        NS_FATAL_ERROR("cannot TX while already TX: the MAC should avoid this");
        break;

    case IDLE: {
        /*
        m_txPsd must be set by the device, according to
        (i) the available subchannel for transmission
        (ii) the power transmission
        */
        NS_ASSERT(m_txPsd);
        NS_LOG_LOGIC(this << " m_txPsd: " << *m_txPsd);

        // we need to convey some PHY meta information to the receiver
        // to be used for simulation purposes (e.g., the CellId). This
        // is done by setting the cellId parameter of
        // LteSpectrumSignalParametersDlCtrlFrame
        ChangeState(TX_UL_SRS);
        NS_ASSERT(m_channel);
        Ptr<LteSpectrumSignalParametersUlSrsFrame> txParams =
            Create<LteSpectrumSignalParametersUlSrsFrame>();
        txParams->duration = UL_SRS_DURATION;
        txParams->txPhy = GetObject<SpectrumPhy>();
        txParams->txAntenna = m_antenna;
        txParams->psd = m_txPsd;
        txParams->cellId = m_cellId;
        m_channel->StartTx(txParams);
        m_endTxEvent = Simulator::Schedule(UL_SRS_DURATION, &LteSpectrumPhy::EndTxUlSrs, this);
    }
        return false;

    default:
        NS_FATAL_ERROR("unknown state");
        return true;
    }
}

void
LteSpectrumPhy::EndTxData()
{
    NS_LOG_FUNCTION(this);
    NS_LOG_LOGIC(this << " state: " << m_state);

    NS_ASSERT(m_state == TX_DATA);
    m_phyTxEndTrace(m_txPacketBurst);
    m_txPacketBurst = nullptr;
    ChangeState(IDLE);
}

void
LteSpectrumPhy::EndTxDlCtrl()
{
    NS_LOG_FUNCTION(this);
    NS_LOG_LOGIC(this << " state: " << m_state);

    NS_ASSERT(m_state == TX_DL_CTRL);
    NS_ASSERT(!m_txPacketBurst);
    ChangeState(IDLE);
}

void
LteSpectrumPhy::EndTxUlSrs()
{
    NS_LOG_FUNCTION(this);
    NS_LOG_LOGIC(this << " state: " << m_state);

    NS_ASSERT(m_state == TX_UL_SRS);
    NS_ASSERT(!m_txPacketBurst);
    ChangeState(IDLE);
}

void
LteSpectrumPhy::StartRx(Ptr<SpectrumSignalParameters> spectrumRxParams)
{
    NS_LOG_FUNCTION(this << spectrumRxParams);
    NS_LOG_LOGIC(this << " state: " << m_state);

    Ptr<const SpectrumValue> rxPsd = spectrumRxParams->psd;
    Time duration = spectrumRxParams->duration;

    // the device might start RX only if the signal is of a type
    // understood by this device - in this case, an LTE signal.
    Ptr<LteSpectrumSignalParametersDataFrame> lteDataRxParams =
        DynamicCast<LteSpectrumSignalParametersDataFrame>(spectrumRxParams);
    Ptr<LteSpectrumSignalParametersDlCtrlFrame> lteDlCtrlRxParams =
        DynamicCast<LteSpectrumSignalParametersDlCtrlFrame>(spectrumRxParams);
    Ptr<LteSpectrumSignalParametersUlSrsFrame> lteUlSrsRxParams =
        DynamicCast<LteSpectrumSignalParametersUlSrsFrame>(spectrumRxParams);
    if (lteDataRxParams)
    {
        m_interferenceData->AddSignal(rxPsd, duration);
        StartRxData(lteDataRxParams);
    }
    else if (lteDlCtrlRxParams)
    {
        m_interferenceCtrl->AddSignal(rxPsd, duration);
        StartRxDlCtrl(lteDlCtrlRxParams);
    }
    else if (lteUlSrsRxParams)
    {
        m_interferenceCtrl->AddSignal(rxPsd, duration);
        StartRxUlSrs(lteUlSrsRxParams);
    }
    else
    {
        // other type of signal (could be 3G, GSM, whatever) -> interference
        m_interferenceData->AddSignal(rxPsd, duration);
        m_interferenceCtrl->AddSignal(rxPsd, duration);
    }
}

void
LteSpectrumPhy::StartRxData(Ptr<LteSpectrumSignalParametersDataFrame> params)
{
    NS_LOG_FUNCTION(this);
    switch (m_state)
    {
    case TX_DATA:
    case TX_DL_CTRL:
    case TX_UL_SRS:
        NS_FATAL_ERROR("cannot RX while TX: according to FDD channel access, the physical layer "
                       "for transmission cannot be used for reception");
        break;
    case RX_DL_CTRL:
        NS_FATAL_ERROR("cannot RX Data while receiving control");
        break;
    case IDLE:
    case RX_DATA:
        // the behavior is similar when
        // we're IDLE or RX because we can receive more signals
        // simultaneously (e.g., at the eNB).
        {
            // To check if we're synchronized to this signal, we check
            // for the CellId which is reported in the
            //  LteSpectrumSignalParametersDataFrame
            if (params->cellId == m_cellId)
            {
                NS_LOG_LOGIC(this << " synchronized with this signal (cellId=" << params->cellId
                                  << ")");
                if ((m_rxPacketBurstList.empty()) && (m_rxControlMessageList.empty()))
                {
                    NS_ASSERT(m_state == IDLE);
                    // first transmission, i.e., we're IDLE and we
                    // start RX
                    m_firstRxStart = Simulator::Now();
                    m_firstRxDuration = params->duration;
                    NS_LOG_LOGIC(this << " scheduling EndRx with delay "
                                      << params->duration.As(Time::S));
                    m_endRxDataEvent =
                        Simulator::Schedule(params->duration, &LteSpectrumPhy::EndRxData, this);
                }
                else
                {
                    NS_ASSERT(m_state == RX_DATA);
                    // sanity check: if there are multiple RX events, they
                    // should occur at the same time and have the same
                    // duration, otherwise the interference calculation
                    // won't be correct
                    NS_ASSERT((m_firstRxStart == Simulator::Now()) &&
                              (m_firstRxDuration == params->duration));
                }

                ChangeState(RX_DATA);
                if (params->packetBurst)
                {
                    m_rxPacketBurstList.push_back(params->packetBurst);
                    m_interferenceData->StartRx(params->psd);

                    m_phyRxStartTrace(params->packetBurst);
                }
                NS_LOG_DEBUG(this << " insert msgs " << params->ctrlMsgList.size());
                m_rxControlMessageList.insert(m_rxControlMessageList.end(),
                                              params->ctrlMsgList.begin(),
                                              params->ctrlMsgList.end());

                NS_LOG_LOGIC(this << " numSimultaneousRxEvents = " << m_rxPacketBurstList.size());
            }
            else
            {
                NS_LOG_LOGIC(this << " not in sync with this signal (cellId=" << params->cellId
                                  << ", m_cellId=" << m_cellId << ")");
            }
        }
        break;

    default:
        NS_FATAL_ERROR("unknown state");
        break;
    }

    NS_LOG_LOGIC(this << " state: " << m_state);
}

void
LteSpectrumPhy::StartRxDlCtrl(Ptr<LteSpectrumSignalParametersDlCtrlFrame> lteDlCtrlRxParams)
{
    NS_LOG_FUNCTION(this);

    // To check if we're synchronized to this signal, we check
    // for the CellId which is reported in the
    // LteSpectrumSignalParametersDlCtrlFrame
    uint16_t cellId;
    NS_ASSERT(lteDlCtrlRxParams);
    cellId = lteDlCtrlRxParams->cellId;

    switch (m_state)
    {
    case TX_DATA:
    case TX_DL_CTRL:
    case TX_UL_SRS:
    case RX_DATA:
    case RX_UL_SRS:
        NS_FATAL_ERROR("unexpected event in state " << m_state);
        break;

    case RX_DL_CTRL:
    case IDLE:

        // common code for the two states
        // check presence of PSS for UE measuerements
        if (lteDlCtrlRxParams->pss)
        {
            if (!m_ltePhyRxPssCallback.IsNull())
            {
                m_ltePhyRxPssCallback(cellId, lteDlCtrlRxParams->psd);
            }
        }

        // differentiated code for the two states
        switch (m_state)
        {
        case RX_DL_CTRL:
            NS_ASSERT_MSG(m_cellId != cellId, "any other DlCtrl should be from a different cell");
            NS_LOG_LOGIC(this << " ignoring other DlCtrl (cellId=" << cellId
                              << ", m_cellId=" << m_cellId << ")");
            break;

        case IDLE:
            if (cellId == m_cellId)
            {
                NS_LOG_LOGIC(this << " synchronized with this signal (cellId=" << cellId << ")");

                NS_ASSERT(m_rxControlMessageList.empty());
                m_firstRxStart = Simulator::Now();
                m_firstRxDuration = lteDlCtrlRxParams->duration;
                NS_LOG_LOGIC(this << " scheduling EndRx with delay "
                                  << lteDlCtrlRxParams->duration);

                // store the DCIs
                m_rxControlMessageList = lteDlCtrlRxParams->ctrlMsgList;
                m_endRxDlCtrlEvent = Simulator::Schedule(lteDlCtrlRxParams->duration,
                                                         &LteSpectrumPhy::EndRxDlCtrl,
                                                         this);
                ChangeState(RX_DL_CTRL);
                m_interferenceCtrl->StartRx(lteDlCtrlRxParams->psd);
            }
            else
            {
                NS_LOG_LOGIC(this << " not synchronizing with this signal (cellId=" << cellId
                                  << ", m_cellId=" << m_cellId << ")");
            }
            break;

        default:
            NS_FATAL_ERROR("unexpected event in state " << m_state);
            break;
        }
        break; // case RX_DL_CTRL or IDLE

    default:
        NS_FATAL_ERROR("unknown state");
        break;
    }

    NS_LOG_LOGIC(this << " state: " << m_state);
}

void
LteSpectrumPhy::StartRxUlSrs(Ptr<LteSpectrumSignalParametersUlSrsFrame> lteUlSrsRxParams)
{
    NS_LOG_FUNCTION(this);
    switch (m_state)
    {
    case TX_DATA:
    case TX_DL_CTRL:
    case TX_UL_SRS:
        NS_FATAL_ERROR("cannot RX while TX: according to FDD channel access, the physical layer "
                       "for transmission cannot be used for reception");
        break;

    case RX_DATA:
    case RX_DL_CTRL:
        NS_FATAL_ERROR("cannot RX SRS while receiving something else");
        break;

    case IDLE:
    case RX_UL_SRS:
        // the behavior is similar when
        // we're IDLE or RX_UL_SRS because we can receive more signals
        // simultaneously at the eNB
        {
            // To check if we're synchronized to this signal, we check
            // for the CellId which is reported in the
            // LteSpectrumSignalParametersDlCtrlFrame
            uint16_t cellId;
            cellId = lteUlSrsRxParams->cellId;
            if (cellId == m_cellId)
            {
                NS_LOG_LOGIC(this << " synchronized with this signal (cellId=" << cellId << ")");
                if (m_state == IDLE)
                {
                    // first transmission, i.e., we're IDLE and we
                    // start RX
                    NS_ASSERT(m_rxControlMessageList.empty());
                    m_firstRxStart = Simulator::Now();
                    m_firstRxDuration = lteUlSrsRxParams->duration;
                    NS_LOG_LOGIC(this << " scheduling EndRx with delay "
                                      << lteUlSrsRxParams->duration);

                    m_endRxUlSrsEvent = Simulator::Schedule(lteUlSrsRxParams->duration,
                                                            &LteSpectrumPhy::EndRxUlSrs,
                                                            this);
                }
                else if (m_state == RX_UL_SRS)
                {
                    // sanity check: if there are multiple RX events, they
                    // should occur at the same time and have the same
                    // duration, otherwise the interference calculation
                    // won't be correct
                    NS_ASSERT((m_firstRxStart == Simulator::Now()) &&
                              (m_firstRxDuration == lteUlSrsRxParams->duration));
                }
                ChangeState(RX_UL_SRS);
                m_interferenceCtrl->StartRx(lteUlSrsRxParams->psd);
            }
            else
            {
                NS_LOG_LOGIC(this << " not in sync with this signal (cellId=" << cellId
                                  << ", m_cellId=" << m_cellId << ")");
            }
        }
        break;

    default:
        NS_FATAL_ERROR("unknown state");
        break;
    }

    NS_LOG_LOGIC(this << " state: " << m_state);
}

void
LteSpectrumPhy::UpdateSinrPerceived(const SpectrumValue& sinr)
{
    NS_LOG_FUNCTION(this << sinr);
    m_sinrPerceived = sinr;
}

void
LteSpectrumPhy::AddExpectedTb(uint16_t rnti,
                              uint8_t ndi,
                              uint16_t size,
                              uint8_t mcs,
                              std::vector<int> map,
                              uint8_t layer,
                              uint8_t harqId,
                              uint8_t rv,
                              bool downlink)
{
    NS_LOG_FUNCTION(this << " rnti: " << rnti << " NDI " << (uint16_t)ndi << " size " << size
                         << " mcs " << (uint16_t)mcs << " layer " << (uint16_t)layer << " rv "
                         << (uint16_t)rv);
    TbId_t tbId;
    tbId.m_rnti = rnti;
    tbId.m_layer = layer;
    auto it = m_expectedTbs.find(tbId);
    if (it != m_expectedTbs.end())
    {
        // might be a TB of an unreceived packet (due to high propagation losses)
        m_expectedTbs.erase(it);
    }
    // insert new entry
    tbInfo_t tbInfo = {ndi, size, mcs, map, harqId, rv, 0.0, downlink, false, false};
    m_expectedTbs.insert(std::pair<TbId_t, tbInfo_t>(tbId, tbInfo));
}

void
LteSpectrumPhy::RemoveExpectedTb(uint16_t rnti)
{
    NS_LOG_FUNCTION(this << rnti);
    TbId_t tbId;
    tbId.m_rnti = rnti;
    // Remove TB of both the layers
    for (uint8_t i = 0; i < 2; i++)
    {
        tbId.m_layer = i;
        auto it = m_expectedTbs.find(tbId);
        if (it != m_expectedTbs.end())
        {
            m_expectedTbs.erase(it);
        }
    }
}

void
LteSpectrumPhy::EndRxData()
{
    NS_LOG_FUNCTION(this);
    NS_LOG_LOGIC(this << " state: " << m_state);

    NS_ASSERT(m_state == RX_DATA);

    // this will trigger CQI calculation and Error Model evaluation
    // as a side effect, the error model should update the error status of all TBs
    m_interferenceData->EndRx();
    NS_LOG_DEBUG(this << " No. of burts " << m_rxPacketBurstList.size());
    NS_LOG_DEBUG(this << " Expected TBs " << m_expectedTbs.size());
    auto itTb = m_expectedTbs.begin();

    // apply transmission mode gain
    NS_LOG_DEBUG(this << " txMode " << (uint16_t)m_transmissionMode << " gain "
                      << m_txModeGain.at(m_transmissionMode));
    NS_ASSERT(m_transmissionMode < m_txModeGain.size());
    m_sinrPerceived *= m_txModeGain.at(m_transmissionMode);

    while (itTb != m_expectedTbs.end())
    {
        if (m_dataErrorModelEnabled &&
            !m_rxPacketBurstList
                 .empty()) // avoid to check for errors when there is no actual data transmitted
        {
            // retrieve HARQ info
            HarqProcessInfoList_t harqInfoList;
            if ((*itTb).second.ndi == 0)
            {
                // TB retxed: retrieve HARQ history
                uint16_t ulHarqId = 0;
                if ((*itTb).second.downlink)
                {
                    harqInfoList =
                        m_harqPhyModule->GetHarqProcessInfoDl((*itTb).second.harqProcessId,
                                                              (*itTb).first.m_layer);
                }
                else
                {
                    harqInfoList =
                        m_harqPhyModule->GetHarqProcessInfoUl((*itTb).first.m_rnti, ulHarqId);
                }
            }
            TbStats_t tbStats = LteMiErrorModel::GetTbDecodificationStats(m_sinrPerceived,
                                                                          (*itTb).second.rbBitmap,
                                                                          (*itTb).second.size,
                                                                          (*itTb).second.mcs,
                                                                          harqInfoList);
            (*itTb).second.mi = tbStats.mi;
            (*itTb).second.corrupt = !(m_random->GetValue() > tbStats.tbler);
            NS_LOG_DEBUG(this << "RNTI " << (*itTb).first.m_rnti << " size " << (*itTb).second.size
                              << " mcs " << (uint32_t)(*itTb).second.mcs << " bitmap "
                              << (*itTb).second.rbBitmap.size() << " layer "
                              << (uint16_t)(*itTb).first.m_layer << " TBLER " << tbStats.tbler
                              << " corrupted " << (*itTb).second.corrupt);
            // fire traces on DL/UL reception PHY stats
            PhyReceptionStatParameters params;
            params.m_timestamp = Simulator::Now().GetMilliSeconds();
            params.m_cellId = m_cellId;
            params.m_imsi = 0; // it will be set by DlPhyTransmissionCallback in LteHelper
            params.m_rnti = (*itTb).first.m_rnti;
            params.m_txMode = m_transmissionMode;
            params.m_layer = (*itTb).first.m_layer;
            params.m_mcs = (*itTb).second.mcs;
            params.m_size = (*itTb).second.size;
            params.m_rv = (*itTb).second.rv;
            params.m_ndi = (*itTb).second.ndi;
            params.m_correctness = static_cast<uint8_t>(!(*itTb).second.corrupt);
            params.m_ccId = m_componentCarrierId;
            if ((*itTb).second.downlink)
            {
                // DL
                m_dlPhyReception(params);
            }
            else
            {
                // UL
                params.m_rv = harqInfoList.size();
                m_ulPhyReception(params);
            }
        }

        itTb++;
    }
    std::map<uint16_t, DlInfoListElement_s> harqDlInfoMap;
    for (auto i = m_rxPacketBurstList.begin(); i != m_rxPacketBurstList.end(); ++i)
    {
        for (auto j = (*i)->Begin(); j != (*i)->End(); ++j)
        {
            // retrieve TB info of this packet
            LteRadioBearerTag tag;
            (*j)->PeekPacketTag(tag);
            TbId_t tbId;
            tbId.m_rnti = tag.GetRnti();
            tbId.m_layer = tag.GetLayer();
            itTb = m_expectedTbs.find(tbId);
            NS_LOG_INFO(this << " Packet of " << tbId.m_rnti << " layer "
                             << (uint16_t)tag.GetLayer());
            if (itTb == m_expectedTbs.end())
            {
                continue;
            }

            if (!(*itTb).second.corrupt)
            {
                m_phyRxEndOkTrace(*j);

                if (!m_ltePhyRxDataEndOkCallback.IsNull())
                {
                    m_ltePhyRxDataEndOkCallback(*j);
                }
            }
            else
            {
                // TB received with errors
                m_phyRxEndErrorTrace(*j);
            }

            // send HARQ feedback (if not already done for this TB)
            if ((*itTb).second.harqFeedbackSent)
            {
                continue;
            }

            (*itTb).second.harqFeedbackSent = true;
            if (!(*itTb).second.downlink)
            {
                UlInfoListElement_s harqUlInfo;
                harqUlInfo.m_rnti = tbId.m_rnti;
                harqUlInfo.m_tpc = 0;
                if ((*itTb).second.corrupt)
                {
                    harqUlInfo.m_receptionStatus = UlInfoListElement_s::NotOk;
                    NS_LOG_DEBUG(this << " RNTI " << tbId.m_rnti << " send UL-HARQ-NACK");
                    m_harqPhyModule->UpdateUlHarqProcessStatus(
                        tbId.m_rnti,
                        (*itTb).second.mi,
                        (*itTb).second.size,
                        (*itTb).second.size / EffectiveCodingRate[(*itTb).second.mcs]);
                }
                else
                {
                    harqUlInfo.m_receptionStatus = UlInfoListElement_s::Ok;
                    NS_LOG_DEBUG(this << " RNTI " << tbId.m_rnti << " send UL-HARQ-ACK");
                    m_harqPhyModule->ResetUlHarqProcessStatus(tbId.m_rnti,
                                                              (*itTb).second.harqProcessId);
                }
                if (!m_ltePhyUlHarqFeedbackCallback.IsNull())
                {
                    m_ltePhyUlHarqFeedbackCallback(harqUlInfo);
                }
            }
            else
            {
                auto itHarq = harqDlInfoMap.find(tbId.m_rnti);
                if (itHarq == harqDlInfoMap.end())
                {
                    DlInfoListElement_s harqDlInfo;
                    harqDlInfo.m_harqStatus.resize(m_layersNum, DlInfoListElement_s::ACK);
                    harqDlInfo.m_rnti = tbId.m_rnti;
                    harqDlInfo.m_harqProcessId = (*itTb).second.harqProcessId;
                    if ((*itTb).second.corrupt)
                    {
                        harqDlInfo.m_harqStatus.at(tbId.m_layer) = DlInfoListElement_s::NACK;
                        NS_LOG_DEBUG(this << " RNTI " << tbId.m_rnti << " harqId "
                                          << (uint16_t)(*itTb).second.harqProcessId << " layer "
                                          << (uint16_t)tbId.m_layer << " send DL-HARQ-NACK");
                        m_harqPhyModule->UpdateDlHarqProcessStatus(
                            (*itTb).second.harqProcessId,
                            tbId.m_layer,
                            (*itTb).second.mi,
                            (*itTb).second.size,
                            (*itTb).second.size / EffectiveCodingRate[(*itTb).second.mcs]);
                    }
                    else
                    {
                        harqDlInfo.m_harqStatus.at(tbId.m_layer) = DlInfoListElement_s::ACK;
                        NS_LOG_DEBUG(this << " RNTI " << tbId.m_rnti << " harqId "
                                          << (uint16_t)(*itTb).second.harqProcessId << " layer "
                                          << (uint16_t)tbId.m_layer << " size "
                                          << (*itTb).second.size << " send DL-HARQ-ACK");
                        m_harqPhyModule->ResetDlHarqProcessStatus((*itTb).second.harqProcessId);
                    }
                    harqDlInfoMap.insert(
                        std::pair<uint16_t, DlInfoListElement_s>(tbId.m_rnti, harqDlInfo));
                }
                else
                {
                    if ((*itTb).second.corrupt)
                    {
                        (*itHarq).second.m_harqStatus.at(tbId.m_layer) = DlInfoListElement_s::NACK;
                        NS_LOG_DEBUG(this << " RNTI " << tbId.m_rnti << " harqId "
                                          << (uint16_t)(*itTb).second.harqProcessId << " layer "
                                          << (uint16_t)tbId.m_layer << " size "
                                          << (*itHarq).second.m_harqStatus.size()
                                          << " send DL-HARQ-NACK");
                        m_harqPhyModule->UpdateDlHarqProcessStatus(
                            (*itTb).second.harqProcessId,
                            tbId.m_layer,
                            (*itTb).second.mi,
                            (*itTb).second.size,
                            (*itTb).second.size / EffectiveCodingRate[(*itTb).second.mcs]);
                    }
                    else
                    {
                        NS_ASSERT_MSG(tbId.m_layer < (*itHarq).second.m_harqStatus.size(),
                                      " layer " << (uint16_t)tbId.m_layer);
                        (*itHarq).second.m_harqStatus.at(tbId.m_layer) = DlInfoListElement_s::ACK;
                        NS_LOG_DEBUG(this << " RNTI " << tbId.m_rnti << " harqId "
                                          << (uint16_t)(*itTb).second.harqProcessId << " layer "
                                          << (uint16_t)tbId.m_layer << " size "
                                          << (*itHarq).second.m_harqStatus.size()
                                          << " send DL-HARQ-ACK");
                        m_harqPhyModule->ResetDlHarqProcessStatus((*itTb).second.harqProcessId);
                    }
                }
            }
        }
    }

    // send DL HARQ feedback to LtePhy
    for (auto itHarq = harqDlInfoMap.begin(); itHarq != harqDlInfoMap.end(); itHarq++)
    {
        if (!m_ltePhyDlHarqFeedbackCallback.IsNull())
        {
            m_ltePhyDlHarqFeedbackCallback((*itHarq).second);
        }
    }
    // forward control messages of this frame to LtePhy
    if (!m_rxControlMessageList.empty())
    {
        if (!m_ltePhyRxCtrlEndOkCallback.IsNull())
        {
            m_ltePhyRxCtrlEndOkCallback(m_rxControlMessageList);
        }
    }
    ChangeState(IDLE);
    m_rxPacketBurstList.clear();
    m_rxControlMessageList.clear();
    m_expectedTbs.clear();
}

void
LteSpectrumPhy::EndRxDlCtrl()
{
    NS_LOG_FUNCTION(this);
    NS_LOG_LOGIC(this << " state: " << m_state);

    NS_ASSERT(m_state == RX_DL_CTRL);

    // this will trigger CQI calculation and Error Model evaluation
    // as a side effect, the error model should update the error status of all TBs
    m_interferenceCtrl->EndRx();
    // apply transmission mode gain
    NS_LOG_DEBUG(this << " txMode " << (uint16_t)m_transmissionMode << " gain "
                      << m_txModeGain.at(m_transmissionMode));
    NS_ASSERT(m_transmissionMode < m_txModeGain.size());
    if (m_transmissionMode > 0)
    {
        // in case of MIMO, ctrl is always txed as TX diversity
        m_sinrPerceived *= m_txModeGain.at(1);
    }
    //   m_sinrPerceived *= m_txModeGain.at (m_transmissionMode);
    bool error = false;
    if (m_ctrlErrorModelEnabled)
    {
        double errorRate = LteMiErrorModel::GetPcfichPdcchError(m_sinrPerceived);
        error = !(m_random->GetValue() > errorRate);
        NS_LOG_DEBUG(this << " PCFICH-PDCCH Decodification, errorRate " << errorRate << " error "
                          << error);
    }

    if (!error)
    {
        if (!m_ltePhyRxCtrlEndOkCallback.IsNull())
        {
            NS_LOG_DEBUG(this << " PCFICH-PDCCH Rxed OK");
            m_ltePhyRxCtrlEndOkCallback(m_rxControlMessageList);
        }
    }
    else
    {
        if (!m_ltePhyRxCtrlEndErrorCallback.IsNull())
        {
            NS_LOG_DEBUG(this << " PCFICH-PDCCH Error");
            m_ltePhyRxCtrlEndErrorCallback();
        }
    }
    ChangeState(IDLE);
    m_rxControlMessageList.clear();
}

void
LteSpectrumPhy::EndRxUlSrs()
{
    NS_ASSERT(m_state == RX_UL_SRS);
    ChangeState(IDLE);
    m_interferenceCtrl->EndRx();
    // nothing to do (used only for SRS at this stage)
}

void
LteSpectrumPhy::SetCellId(uint16_t cellId)
{
    m_cellId = cellId;
}

void
LteSpectrumPhy::SetComponentCarrierId(uint8_t componentCarrierId)
{
    m_componentCarrierId = componentCarrierId;
}

void
LteSpectrumPhy::AddRsPowerChunkProcessor(Ptr<LteChunkProcessor> p)
{
    m_interferenceCtrl->AddRsPowerChunkProcessor(p);
}

void
LteSpectrumPhy::AddDataPowerChunkProcessor(Ptr<LteChunkProcessor> p)
{
    m_interferenceData->AddRsPowerChunkProcessor(p);
}

void
LteSpectrumPhy::AddDataSinrChunkProcessor(Ptr<LteChunkProcessor> p)
{
    m_interferenceData->AddSinrChunkProcessor(p);
}

void
LteSpectrumPhy::AddInterferenceCtrlChunkProcessor(Ptr<LteChunkProcessor> p)
{
    m_interferenceCtrl->AddInterferenceChunkProcessor(p);
}

void
LteSpectrumPhy::AddInterferenceDataChunkProcessor(Ptr<LteChunkProcessor> p)
{
    m_interferenceData->AddInterferenceChunkProcessor(p);
}

void
LteSpectrumPhy::AddCtrlSinrChunkProcessor(Ptr<LteChunkProcessor> p)
{
    m_interferenceCtrl->AddSinrChunkProcessor(p);
}

void
LteSpectrumPhy::SetTransmissionMode(uint8_t txMode)
{
    NS_LOG_FUNCTION(this << (uint16_t)txMode);
    NS_ASSERT_MSG(txMode < m_txModeGain.size(),
                  "TransmissionMode not available: 1.." << m_txModeGain.size());
    m_transmissionMode = txMode;
    m_layersNum = TransmissionModesLayers::TxMode2LayerNum(txMode);
}

void
LteSpectrumPhy::SetTxModeGain(uint8_t txMode, double gain)
{
    NS_LOG_FUNCTION(this << " txmode " << (uint16_t)txMode << " gain " << gain);
    if (txMode > 0)
    {
        // convert to linear
        double gainLin = std::pow(10.0, (gain / 10.0));
        if (m_txModeGain.size() < txMode)
        {
            m_txModeGain.resize(txMode);
        }
        m_txModeGain.at(txMode - 1) = gainLin;
    }
}

int64_t
LteSpectrumPhy::AssignStreams(int64_t stream)
{
    NS_LOG_FUNCTION(this << stream);
    m_random->SetStream(stream);
    return 1;
}

} // namespace ns3
